Mufflers, as components of exhaust systems, are well known in the art as used on automobiles and motorcycles. Indeed, due to noise laws and ordinances at both the federal and local level, mufflers are typically required by law to limit exhibited decibel levels during automobile or motorcycle vehicle operation.
In a conventional muffler, sound waves generated by engine operation (e.g., resulting from piston/valve firings) are channeled through an exhaust system, through manifolds or headers, to where they eventually reach an installed muffler. Then, depending on the muffler design, the sounds waves are manipulated or redirected to reduce decibel output. For example, in certain car muffler designs, the muffler is configured to include sound reflective surfaces so that the amplitude of a sound wave encounters the trough of a different sound wave (e.g., one being directionally reversed by reflection), with the resulting effect being that the “sound” is canceled out (in whole or in part). In other muffler types, such as in motorcycles, it is common to employ sound deadening materials, such as steel wool or fiberglass, which “absorb” sound waves and thus also reduce decibel output. While such motorcycle muffler types—known as packed mufflers—are at least marginally effective at sound deadening or decibel reduction, such prior art muffler designs exhibit drawbacks such as exhaust gas back-pressure buildup, which can reduce fuel efficiency or engine performance, and undesirable acoustic characteristics or output levels.
Prior known motorcycle muffler manufacturing processes or techniques also have attendant drawbacks. For example, in prior known techniques to manufacture a tapered style motorcycle muffler, the mufflers were made from flat (planar) sheet steel which was laser cut, roll formed into a cylinder or cone shape, and then welded along a longitudinal seam (spanning the entire length of the muffler) to close and seal the muffler shell. However, laser cutting and roll forming machines are not only expensive but require high degrees of skill to operate. Similarly, the gas tungsten arc welding (aka “TIG” welding) techniques used (conventional for welding thin steel sheets) are more complex and difficult to master (thus labor is more skilled and expensive) and are comparatively slow, thus increasing muffler production time.
Fulfilling certain market desires, aftermarket mufflers are also known in the art and are often produced and used for aesthetic reasons, altering the acoustic characteristics of an exhaust, or for altering performance characteristics. Known aftermarket mufflers such as for motorcycles, however, must be uniquely produced and configured for specific motorcycle makes and models not only to “fit” the existing exhaust connections but also so that the muffler installs at the proper angle and in an appropriate space envelope (such as won't interfere with normal motorcycle operations).
In view of the above-described drawbacks or problems in the art, it is apparent that there exists a need for a muffler or exhaust which addresses, overcomes, mitigates, and/or solves one or more of such problems and/or drawbacks. It is a purpose of the invention(s) disclosed herein to fulfill one or more of these needs in the art and/or other needs which will become more apparent to the skilled artisan once given the following disclosure.